Hey guys, I'm having the hardest time trying to passs emissions ever since I installed speed daddy headers. I got my uncle's shop to weld on some generic cat after installing the headers and no matter what I can't pass emissions. I've got the o2 codes tuned out, but my emissions readiness still says the catalyst is still incomplete. Any recommendations for a good quality cat would be appreciated!
Best cat to use with Speed Daddy headers?
- Thread starter snj111795
- Start date
SgtMarshal
Active member
if it's a 2001 or later, you have to find a way to disable the cat test diagnostic
Scottydoggs
Killa Bee
crap, i just looked at your bin the second 1/2 of the 420 code i missed or it didnt take .
how many miles you put on it so far? it should become ready still cause the o2 codes and tests are not there to tell it to throw the 420 cat code. it just needs to cycle a bunch of times.
how many miles you put on it so far? it should become ready still cause the o2 codes and tests are not there to tell it to throw the 420 cat code. it just needs to cycle a bunch of times.
It's a 2001 GTP. And Scotty, I've put 230miles on it so far. I've done the gm drive cycle where you have to put the ac and defroster on for about 2 and a half mins and drive for ten mins. I've done this three separate times from a cold start. I've got everything to say it's emissions ready /except/ for the catalyst and o2 Sensor. I'll post a pic of my emission diagnostic log in a few minutes.
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http://imgur.com/SyzpJvA Here's a pic of my Emissions Readiness s/DTC.
Scottydoggs
Killa Bee
weren't you having the same issue with the last tuned pcm? my car only shows one 02 sensor, and it also can take a while to become ready, its the up stream o2 you cant delete that one. its the post cat "rear" o2 that gets deleted.
Scottydoggs
Killa Bee
i just loaded up your bin to a spare pcm, tomorrow after work ill hook my t app up to it and see what your seeing as far as im "ready"
Honestly I never checked my emissions readiness with my old pcm. Wish I had now lol. I can understand that the cat would take a little while to show its ready, but any idea why the o2 wouldnt ready by this point? After 230 miles I'm sort of losing hope that it'll fix itself with more miles. I'll go give it another try later on tonight and see if anything changes, but I won't hold my breath.
Also heres a look at my o2 sensor voltages http://imgur.com/RnQnNer. They fluctuated as I drove, within .05 or so. As far as I know they look fine, but figured I'd present that information. Also here a some vehicle test results http://imgur.com/CqoyXhn. The code TID: $05 CID:$0a was not working properly, infact it was the only code that wasnt working properly. Its the rich to lean sensor switch and it hasnt calculated anything at all. Any ideas on what might be the cause? I'm thinking this is maybe one of the reasons why o2 wont show its ready yet. But I havent got a clue. If theres any more information needed I can try to provide more.
Scottydoggs
Killa Bee
the up stream o2 should be dancing up and down with its volts, .1 to .8 over and over and over. pretty sure thats your switching time. so you might need a new o2. is this the stock o2 your still using?
I'll go take a look and see if it fluctuates like you said. And yes it's a stock sensor, so its likely due for replacement. I'll order one from rock auto and keep you guys updated.
Scottydoggs
Killa Bee
if its sitting at one voltage when at idle, the o2 is lazy. at idle, it should dance up and down. it should always be on the move really.
So I've put a few hundred miles on the car after the new o2 install and still my o2 and car say they're not ready. So now I'm convinced this something that throwing parts at just won't fix. Scotty, you think you can check my pcm out and see if there's anything funky going on? If not, then I'm about ready to just call this car a lost cost and move on.
Scottydoggs
Killa Bee
send it over, ill go over it again. and ship it back for free.